Implantable medical devices are commonly used to perform a variety of functions, such as to monitor one or more conditions and/or delivery therapy to a patient. In some cases, an implantable medical device may deliver neurostimulation therapy to a patient. In some cases, an implantable medical device may simply monitor one or more conditions, such as pressure, acceleration, cardiac events, and may communicate the detected conditions or events to another device, such as another implantable medical device or an external programmer.
In some cases, an implantable medical device may be configured to deliver pacing and/or defibrillation therapy to a patient. Such implantable medical devices may treat patients suffering from various heart conditions that may result in a reduced ability of the heart to deliver sufficient amounts of blood to a patient's body. In some cases, heart conditions may lead to rapid, irregular, and/or inefficient heart contractions. To help alleviate some of these conditions, various devices (e.g., pacemakers, defibrillators, etc.) may be implanted into a patient's body. When so provided, such devices can monitor and provide therapy, such as electrical stimulation therapy, to the patient's heart to help the heart operate in a more normal, efficient and/or safe manner. In some cases, a patient may have multiple implanted devices that cooperate to monitor and/or provide therapy to the patient's heart.
In some cases, implantable medical devices must be relatively small. For example, leadless cardiac pacemakers are typically relatively small because they are often placed within the heart. Due to their relatively small size, a large fraction of the internal space of such implantable medical devices may be consumed by a battery or other power source. As the battery life determines the potential useful life expectancy of the implantable medical device, there is a desire to make the batteries as large as possible within the confines of the available space.
What would be desirable is an implantable medical device that has recharge capability for recharging a rechargeable power source of the implantable medical device. This may give the implantable medical device a longer useful life expectancy and/or may not require as much battery space permitting a significantly smaller device size. A smaller device size may make the device more easily deliverable and implantable in the body, allow the device to be implantable in smaller and more confined spaces in the body, and/or may make the device less expensive to produce.